Sheet-metal-bending machine



W. BITTNER SHEET METAL BENDING MACHINE Nov. 13, 1928. 1,691,032

Filed Dec. 50, 1927 2 Sheets-Sheet 1 FIG. 2

INVENTOR WILL/AM 517mm ATTORNEY Nov. 13, 1928.

w. BITTNER SHEET METAL BENDING MACHINE Filed Dec. :50, 1927 2Sheets-Sheet 2 .9

llllllllll INVENTOR WILL/AM B/ TTNER hzr w A TTORNE Y Patented Nov. 13,1928.

WILLIAM BITTNER, or BRO KLYN, NEW YoRK.

SHEET-METAL-BENDING MACHINII.

Application filed December 30, 1927. Serial No. 243,674.

My invention relates to a machine .used for the purpose of bending theedges of thin sheet metal. In the sheet metal trade, it is necessary tomake a great many joints, and

to do this the edges of the metal must be bent substantially at-rightangles to the main body portion of the sheet, and so far as I am awarethere is no machine thatwill :do this work, in one operation.

In my Patent 1,613,307, issued January 4th,

1927, I have shown and described amachine which will do the work in twooperations, and after considerable study of the problem and manyexperiments, I' have discovered means of bending the edge of the metalsubstantially at right angles to the rest ofthe sheet in one pass of themetal through the machine; and it is therefore the principal object ofmy invention to provide a machine which will accomplish this purpose,thereby saving a tremendous lot of time in the for1ning of the edges ofthe sheet metal. Another object of my invention is to provide a devicewhich will do this work,'that is relatively simple and inexpensive infirst cost, and upkeep.

Another object of my invention is to provide a machine which may bereadily replaced in whole, or in part by a new apparatus or partsthereof.

These and other objects will be apparent to one skilled in the artofsheet'meta-l working after a study of the specification taken inconnection with the annexed drawing, wherein, Figure lis a plan view ofthe top of the machine, showing the cover of the bending device per sein open position.

Figure 2 is a side elevation of the complete machine, showing thedriving motor and the driving motor coupling the switch and connectinggear mechanism. 9

Figure 3 is a view on a reduced scale, but

larger than that shown in Figures 1 and 2, of the unitary structurewhich is used in bending the metal.

Figure 4 is a plan view of the bending'rolls and an auxilliary bendingdevice, used with the bending rolls. i

Figure 5 is a part sectional view substantially full size through theunitary bending structure, with certain parts removed, those shown beingsubstantially full size.

edge is rolled up to the Figure is an enlarged view of the auxilllaryforming device used with the rolls, the

view being an elevation looking at Figure at w from the bottom of thesheet toward the top.

Figure? is a perspective view of the top end of Figure 6 turned at 180degrees.

Figure 8 is an end view of a piece of sheet metal coming from themachine, while Figure 9.is a plan viewshowing how the ure 8.

Referring now to the details wherein like numbers refer to correspondingparts inthe various views: 1 is a stand preferably made of structuralsteel, having a substantially flat top2 of any suitable material, suchas cast iron. Mounted on the bottom of the top 2 is an electric motor 3,operated by a switch or controller 4, The motor shaft, by means of acoupling 5, is connected to apair of worm gears housed within thehousing 6. From the gear case 6 extends a shaft 7 upwardly through thetable top 2. I

The important part of my machineres'ides in the unitary structuremounted on the to of the table; This comprises a housingS pre, erablyhaving a cover or lid 9, hinged to the housing 8, in any suitablemanner, as by pivot bolt 10 which passes through lugs on both thehousing and the cover, which keeps position shown in Fig foreignmaterial from getting in between the gears and also preventing theoperator from acc dentally gett ng caught in the gears.

The bottom side of the housing 8 is ma chined off to provide a seat 11,which fits on the top 2, and is held thereto by a pair of bolts'12,Adjacent the seat 11, the housing is machined out at13, to provide aspace or seat for the forming roll 14, the seat 13 having sufli'cientdepth, so that the face of the formingroll 14:, is slightly belowtheseat 11 of the housing, so that the roll does not engage the stand top2. The roll 14 referably has a hub 15, extending through tie wall of thehousing 16, and fitting snugly therein so as to act as a guide andsupport for the forming roller 14. The hub 15 has a keyway' 17, to keythe hub 15 to the driving shaft 7, on

is used to hold the gear 18 in position. It will be noted from Figure 3that the inner surface of the wall of the housing is machined at toprovide a free running space for the gear 18. I

Adjacent the cut away portion 13, which is provided for the forming roll14,.the bottom of the housing, represented by the line 21 is cut away atan angle, and positioned substantially at right angles to this annularportion 21. there is mounted through the wall '16 of the housing, a stubshaft 22, on the outer end of which is carried a forming roller 23, andwithin the housing a gear, 24 is keyed to the stub shaft and held inposition thereon by a nut 25. The stub shaft is carried in a hearingbushing 26, preferably made of a good quality of brass or bronze. Thebushing 26 is preferably in the form shown in Figure 4, and against theflat face 27, there is positioned the plate 28 preferably of steel,which is engaged by an adjusting screw 29,.carried in a bushing 30,supported in the wall ofthe housing. After the adjusting screw 29 hasbeen set as hereinafter explained, it is locked in position by as'etscrew 39 see Figure To the outer end of the adjusting screw 29, isfastened an adjusting member 31, on which is carried an indicator 32,calibrated at to indicate the thickness of the sheet. metal to be passedbetween the forming roll. After the indicator 32 has been set to theproper.

point, as will be hereinafter described it is locked in place by a setscrew 34. On account of the stub shaft 22 and its gear 24, and formingroll 23 being set at an angle the two gears 18 and 24 are tapered toaccommodate this position of mounting of the stub shaft. As will benoted from Figures 3 and 5, the forming roll 23-has a tapered knurledperipheral edge, the lmurling being provided for the purpose of grippingthe metal so as to draw it between the two rolls 14 and 23.

I have found thissetting of the stub shaft on the forming roller 23 tobe necessary in order to bend the edge of the metal at right angles,-andas a further essential feature, I have found it necessary to useaforming device, which comprises a stud 35 made of a suitable grade ofsteel, which may be posi .tioned in the top 2, as shown in Figures 3 andFrom Figure 4, it will be seen that the forming device 35 is positionedto one side of the central line oining the-two rolls 14 and. 23, and hasan end. especially formed and projecting between the peripheral edgesofthe roll er. One side of this specially shaped end is arcuately cut at86 to substantially the same are as the forming roller 14, and as shownin Figure 4, has a clearance from the edge of the roll 14. ofapproximately five thousandths of an inch. The other side 37 of saidprojecting end is peculiarly formed in a. manner which I have determinedby experiment to be the best for holding the edge of the sheet metal insuch a position as to start it curving as indi-- cated in Figures 8 and9, and as the roll 23 due to its knurled surfacedrags the metal throughbetween the rolls 14 and 23, the forming device just indicated start-sthe bending operation and holds the metal in such a position that-therolls perform the rest of the work. 7

As has been indicated the stub shaft 22, its gear 24 and forming roll 23may be adjusted bodily in a lateral direction by the adjusting mechanismdescribed, and by means of the gauge the rollsmay be set with respect toeach other to accommodate various thicknesses of metalwithin a given rane, for a given size of the unitary device. As will be seen from Figures3 and 5, the forming roll 23, is positioned in a different plane fromthe forming roll 14 and there is a clearance below theface of theforming roll for the sheet of metal being operated on, to pass beneaththe forming roll and housing.

While I have shown the forming device 35 as mounted in the table top 2,it may be positioned in the wall 16 of the housing 8. When mounted as inFigure 5, in the stand top 2 it may be put in by a pressed fit sothat itwill not shift in position, but in order to remove it for fitting in anew one, the stud 38 is provided for forcing the forming device 35 outof the top 2.

I have found that my object is obtained, that is to say, the edge of themetal is bent at right angles, when the stub-shaft 22 and its associatedforming roll 23, are set at an angle of approximately seven and one halfdegrees and when so set, I prefer to divide the taper on the two gears18 and 24 evenly, it being.

understood that the teeth on these gears are of suflicient' depth toallow for the lateral displacement of the'stub shaft and its parts toaccommodate various gauges of sheet metal. In thedevice shown this willform sheet metal up to approximately fort-y thousandths of an inchthick; and for heavier gauges the parts of course, are proportionatelyenlarged, or changed to meet the condi tion of thicker metal, or an edgewider than that which is to be formed in the particular device shown,and described herein. All of these changes and others indicate that thedetails may be varied over considerable range, without departing fromthe spirit of the invention and the scope of the appended claims. Havingthus described my invention, what I claim is: p

l 1. In a sheet metal bending machine, at least two rolls spaced apart,means for driving said rolls, means associated withat least one of saidrolls for drawing a sheet of metal so that a portion passes between saidrolls, and a forming device positioned between the peripheries of saidrolls and to one side of the line joining their centers, said formingdevice extending so as to intersect the planes of said ing said rolls,

one of said rolls for drawing a sheet of metal g on the stub shaft beingsomewhat rolls and having a face contour which functioning with therolls, turns the edge of the metal to the desired. angle. 7

2. In a sheet metal bending machine, at least two rolls, spaced apart,means for drivmeans associated with at least so a portion passes betweensaid rolls, means for adjusting at least one of said rolls with respectto the other to accommodate sheets of varying thickness and a formingdevice positioned between the peripheries of said rolls and to one sideof the line joining their centers, said forming device extending so asto intersect the planes of said rolls and having a face contour whichfunctioning with the rolls, turns the edge of the metal to the desiredangle.

3. In a sheet metal bending machine, at least two rolls spaced apart,and having their axes set at an angle to each other, means fordrivingsaid rolls, means for quickly adjuste ing the distance betweensaid axes to operate on sheets of varying thickness, means asso ciatedwith theadjustable roll for drawing a sheet of metal so a portion passesbetween said rollsiand a forming device positioned between theperipheries of said rolls and to one side of the line joining theircenters, said forming device extending so as to intersect the planes ofsaid rolls and having a face contour which functioning with the rolls,turns the edge of the metal to the desiredangle.

4. In a sheetmetal bending machine, a

driving shaft having a gear and'roll thereon,

a stub shaft having a gear in mesh with the gear on the driving shaftand a roll adjacent the first roll, said stub shaft being set at anangle with respect to the drive shaft, whereby the plane of the rollthereon is at an angle to the plane of the roll on the'driving shaft,said stub shaft with its gear and roll being bodily adjustable laterallywith respect to the driving shaft, its gear and roll, means associatedwith'one of said rolls for driving sheet metal therebetween, and aforming device poistioned between the peripheries of said rolls butoffset from a straight line joining the centers of said rolls andcooperating with said rolls to turn the edge of the metal substantiallyat right angles to the rest of the sheet. i

5. In a sheet metal bending machine, a driving shaft having a gear androll thereon a stub shaft having a gear in mesh with the gear on thedriving shaft and a roll adjacent the first roll, said stub shaft beingset at an angle with respect to the drive shaft, said roll elevatedabove the first roll and having its plane at an angle to the plane ofthe first roll and having means for drawing metal between it and thefirst roll, means for shifting the stub shaft with its gear androlllaterally with respect to the driving shaft for the purpose described,and a. device. having especially formed end extending betweensaid rollsand cooperating with them to turn the edge of the metal to the desiredangle. 6. A machine for bendingithe edge of thin metal comprising astand having a fiat top and carrying a suitable driving means below saidtop, a unitary structure rigidly mounted on the upper part of said top,said unitary structure consisting of a box having a readily removablecover, and havinga seat on its bottom side,

at one end to fiton said.

stand top and a cut away portion adjacent said seat and a furtherportion cut at an angle to the first cut away portion, a rollpositioned. in the first cut away portion, a driving shaft extendingfrom said driving means to the interior of said box, a gear within thebox and rotated by the driving shaft, a stub shaft carcarried by thatpart of the box having the portion cut at an angle, and having agearthereon within the box driven by the first gear and a rollpositioned adjacent said angular out part of the box and close to thefirst mentioned roll, and between said rolls and cooperating therewithto turn the edge ofthe metal as it is drawn by the rolls beneath saidbox.

7. A unitary edge of thin metal consistingof a box like housing having aportion of one side finished to form a seat for fastening it to asupport said housing having a cutaway portion adsaid cut away formingroll adapted to be driven by a suitabledriving means, a gear wheelwithin the housing operated by said drivingmeans, a stub shaft carriedby said housing, a gear wheel on-the stubshaft within the housing andadapted to be driven L wheel, a forming roll on the stub shaft andpositioned exterior ofthe housing adjacent the first roll but in adifferent plane and havingclearance between its outer face and the Isupport for the purpose described, and a forming device having a specialshaped end positioned between said guide and assist in turning the edgeof the metal substantially as described, as the edge passes betweentherolls. 8 A

edge of thin'metal consisting of a box like housing having a portion ofone side finished to form a seat, a support to receive said seat,saidhOusinghaVinga cut away portion adjacent said seat, a forming rollpositioned in said cut away portion, a suitable driving means forvdriving said roll, a gear wheel withinthe housing operated by saiddriving means, a stub shaft carried by said housing, a gear wheel on thestub shaft within the housing and adapted to be drivenby the first gearwheel, ajforming roll on the stub shaft and positioned, exterior of thehousing adforming device positioned structure for bending the by thefirst gearforming rolls to unitary structure for bending the lib l in

jacent the first rollbut in a different plane and having clearancebetween its outer face and thesupport for the purpose described, meansfor quickly adjusting the distance between said forming rolls to receivematerial of varying thickness, means associated with at least one ofsaid rolls for drawing the material between them, and a forming devicehaving a special shaped end positioned between said forming rolls toguide and assist in turning the edge of the metal substantially asdescribed as the edge passes between the rolls.

i). A. unitary structure for bending the edge of thin metal consistingof a box like housing having a portion of one side finished to form aseat, a support to receive saidseat, said housing having a cut awayportion adjacent said seat, a forming roll positioned in said cut awayportion, a suitable driving means for driving said roll, a gear wheelwith in the housing operated by said driving means,- and a stub shaftcarried by said housing, a gear wheel on the stub shaft within thehousing and adapted to be driven by the first gear wheel, a forming rollon the stub shaft and positioned exterior of the'housing adiacent thefirst roll but in a different plane and having clearance between itsouter face a and the support for the purpose described,- manuallyoperable means extending without the housing for shifting laterally saidstub shaft with its gear and roll for the purpose described, said latterroll having its peripheral edge knurled to draw the material between therolls, and a forming device having a special shaped end positionedbetween said forming rolls to guide and assist in turning the edge ofthe metal substantially as described, as the edge passes between therolls.

10. A unitary structure for bending the edge of thin metal consisting ofa boxlike housing having a portion of one side finished to form saidhousing having a cut away portion adjacent said seat, a forming rollpositioned in said cut away portion, a suitable driving means fordriving said roll, a'gear wheel within the housing operated by saiddriving means, a stub shaft carried by said housing at a small anglediverging outwardly from the axis of said gear wheel and roll, a gearwheel on the stub shaft within the housing, both said gear wheels beingslightly tapered to properly mesh on account of said angular setting ofsaid stub shaft, a forming roll on the stub shaft and positionedexterior of the housing adjacent the first roll andhaving clearancebetween its outer face and the support for the purpose described, meansfor quickly shifting laterally-the stub shaft its gear and roll, saidlatter roll having its peripheral edge tapered toward the housing andknurled for the purposes described and a forming device having a specialshaped end a seat, a support to receive said seat,

positioned between said forming rolls to guide and assist in turning theedge of the metal substantially as described, as the edge passes betweenthe rolls.

11. A unitary structure for bending the edge of thin metal consisting ofa boxlike *housing having a portion of one side finished ,to form aseat, a support to receive said seat, a gear wheel and a forming rollpositioned, the gear within the housing and the roll without, a drivingshaft to operate both the gear wheel and the roll, a stub shaft car-'rying a gear wheel within the housing in mesh with the first gear and aforming roll with out the housing to co-operate with the first roll,said stub shaft] being set at a small angle to said driving shaft andlaterally adjustable with respect thereto, said housing being cut awayso the roll on the stub shaf is clear from the support to allow thematerial to be bent to pass thereunder, said last mentioned roll havinga tapered knurled edge for the purposes described, and a forming devicehaving a special shaped enr positioned between said forming rolls toguide and assist in turning the edge of the metal substantially asdescribed as the edge passes betweenthe rolls.

12. A unitary structure for bending the edge of thin metal consisting ofa box like housing having a portion of one side finished to form a seat,a support to receive said seat, a driving gear and a driven gear withinthe housing, a pair of forming rolls posi' 'tioned outside saidhousingand associated one each with each of said gear wheels, a driving shaftfor operating one of said gears and its associated roll, a stub shaftcarrying the othergear wheel and its associated roll, said lastmentioned roll being in a different plane than the other roll and havinga tapered knurled edge for the purposes described, and a forming devicehaving a special shaped end positioned between said forming rolls toguide and assist in turning the edge of the metal substantially asdescribed as the edge passes between the rolls. 7 1.3. A unitarystructure for bending the edge of sheet metal comprising a housir a infeed table, at least a driving and a driven gear within the housing, adriving member to 0p- 7 crate the driving gear, a forming roll operatedby the driving member, a second forming roll operated through the mediumof the driven gear, said forming rolls being disposed' outside thehousing and in different planes, the second roll being spaced away fromthe feed table so the stock may pass beneath the roll, and a formingdevice cooperating with said rolls to guide the stock and assist inturning the edge. 7

14. A unitary structure for bending the edge of sheet metal comprising ahousing, a feed table, at least a driving and a driven gear within thehousing, a driving member till Ill)

to operate the driving gear, a forming roll knurled edge to draw thestock between the operated by the driving member, a second rolls, meansfor adjusting the space between 10 forming roll operated through themedium theforming rolls and a forming device 00- of the driven gear,said forming rolls being operating With said rolls to guide the stock 5disposed outside the housing and in differand assist in turning theedge.

ent planes, the secondroll being spaced away In testimony whereof, IafiiX my signature. from the feed table, so the stock may pass beneaththe roll, and having a tapered WILLIAM BIITTNER.

